Coffee-making apparatus

ABSTRACT

A coffee-making apparatus comprising an electric throughflow heater, connected to a water reservoir, is switched on and off in dependence on the water level by means of a swiveling float incorporating a mercury switch.

United States Patent Inventor Gerard Clement Smit Utreehtse Straatweg26, Amerongen, Netherlands Appl. Np. 823,443

Filed May 9, 1969 Patented Nov. 9, 1971 Priority June 20, 1968Netherlands 6,808,675

COFFEE-MAKING APPARATUS 1 Claim, 4 Drawing Figs. I

US. Cl 219/333,

Int. Cl F24h 1/08 Field 01 Search ZOO/84.3,

[56] References Cited UNITED STATES PATENTS 2,136,220 11/1938 ShepherdZOO/84.2 UX 2,459,305 1/1949 Brandl 219/333 X 2,580,759 1/1952 GilleZOO/84.2 UX 3,049,987 8/1962 Bampfer.... 99/281 3,291,034 12/1966 Sohnet al. 99/281 X FOREIGN PATENTS 186,346 8/1954 Germany 200/842 UX1,374,961 9/1964 France 219/333 Primary Examiner-David Smith, Jr.AttorneyWalter Becker ABSTRACT: A coffee-making apparatus comprising anelectric throughflow heater, connected to a water reservoir, is switchedon and off in dependence on the water level by means of a swivelingfloat incorporating a mercury switch.

COFFEE-MAKING APPARATUS This invention relates to a cofl'ee-makingapparatus comprising an electric throughflow heater, connected to awater reservoir, for passing hot water to a filter.

Apparatuses of this kind, which are known in various embodiments, areprovided with a mechanism for switching the throughflow heater on andoff. As for as these switch mechanisms are arranged to control theapparatus automatically and in dependence on the presence of water, theyhave hitherto been of a highly vulnerable and unreliably operatingconstruction.

It is an object of the present invention to provide a coffeemakingapparatus having a switch mechanism which is free of the drawbacksreferred to.

According to the invention, there is provided a coffee-making apparatuscomprising an electric throughflow heater, connected to a waterreservoir, for passing hot water to a filter, characterized in that, inthe path of flow of the water to be heated, there is included a chamberhaving a float swiveling about a fixed point and a mercury switch forthe throughflow heater, stationarily mounted in said float. In apreferred embodiment of the invention said float chamber is disposedimmediately subjacent to the water reservoir.

One embodiment of the invention will now be described, by way ofexample, with reference to the accompanying, in which:

FIG. 1 is a vertical longitudinal section of the coffee-making apparatusaccording to the invention;

F IG. 2 is a plan view of the water reservoir; and

FIG. 3 and 4 show vertical longitudinal sections of the float chamberwith the float in different positions.

Referring to the drawings, there is shown a coffee-making apparatuscomprising a baseplate 1 including a heating plate 2 for a filtrate pot3 which carries a removable filter 4.

Secured to the base plate 1 is a housing 5 carrying a water reservoir 6.The bottom of the reservoir 6 has a central column 7 and an eccentricrecessed portion forming a float chamber 8. The float chamber 8 isroofed by a hood 11, the latter being provided with lateral slots 9 anda vent 10. Permanently in communication with the water reservoir 6, thefloat chamber is connected to a tube 12, the lower end of which iscoupled to an electric throughflow heater 13 which, at choice, can beswitched on fully or partly and communicates through a tube extendingthrough the column 7 of the water reservoir with a swiveling horizontaltube 14, whose outlet 15 can be positioned centrally over the filter 4or swung away out of this position.

Disposed in the float chamber 8 is a float 16 secured through a flexibletube 17 to a wall of the float chamber for free up-and-down movementbetween the bottom of the float chamber 8 and the hood 11. The float 16contains a mercury switch 18, which is stationarily mounted therein, andwhose contact points 19 and 20 are connected through leads 21 and 22,housed in the tube 17, to the throughflow heater l3 and to a source ofelectric current.

When the coffee-making apparatus is put into service, the tube 12 andthe heater 13 should be filled with water to just below the floatchamber 8. If, in that condition, in which the float 16 rests on thebottom of the float chamber 8, so that the heater 13 is in itsswitched-off position (FIG. 4), a given quantity of water is poured intothe reservoir 6, a part of this water will immediately fill the floatchamber 8. As a result, the float will swing upwardly and the mercury 23will be displaced to establish an electric connection between thecontact points 19 and 20 (FIG. 3), which puts the heater 13 intooperation. The water in the heater will be brought to the boil, forcedupwardly, and passed through the outlet 15 to the filter 4, while beingreplaced by water from the reservoir 6 and the float chamber 8. As soonas the supply of water is exhausted, so that the float chamber is empty,the float 16 will drop, whereby the displacement of the mercury 23 willbreak the electric connection between the contact points 19 and 20 andswitch off the heater 13.

The simple switch mechanism l6, 18 for controlling the heater can bemade of sturdy construction so that it will be relatively invulnerableand operate reliably.

If so desired, the heater 1:! may be arranged to operate at full or halfcapacity, depending on whether the apparatus is used for the normalfiltering method or for the quick-filtering method. For that purpose, aselection switch 24 can be included in the electric leads connected tothe heater, by means of which the heater can be previously adjusted tooperate at full or half capacity after it has been switch on.Furthermore, a signal lamp 25 can be included in said electric leads toindicate that the heater is actually in its switched-on condition.

I claim:

1. A coffee-making apparatus comprising a hollow housing member, anelectric throughflow heater located in said housing, a water reservoirsupported on the upper end of said housing and having a bottom wallabove said heater, a tube extending upwardly from said heater andcentrally through said reservoir for connection to a horizontal tubehaving an outlet to one side of said reservoir, said bottom wall havingan opening therein, a float chamber below said opening and incommunication with said reservoir, a connection from said float chamberto the bottom of said throughflow heater to pass water from saidreservoir to said heater and out said tube to said outlet, said floatchamber having sidewalls connected to the bottom wall of said reservoir,a hollow float in said float chamber pivotally connected to a sidewallof said chamber by a flexible tubular sleeve fixed to said sidewall andopening through said sidewall, a mercury switch in said float positionedso that pivotal up-and-down movement of said float as said chamber isfilled and emptied will close and open said switch, and lead wirespassing through said tubular sleeve to said switch and connected toenergize said heater when said switch is closed.

I! i l

1. A coffee-making apparatus comprising a hollow housing member, anelectric throughflow heater located in said housing, a water reservoirsupported on the upper end of said housing and having a bottom wallabove said heater, a tube extending upwardly from said heater andcentrally through said reservoir for connection to a horizontal tubehaving an outlet to one side of said reservoir, said bottom wall havingan opening therein, a float chamber below said opening and incommunication with said reservoir, a connection from said float chamberto the bottom of said throughflow heater to pass water from saidreservoir to said heater and out said tube to said outlet, said floatchamber having sidewalls connected to the bottom wall of said reservoir,a hollow float in said float chamber pivotally connected to a sidewallof said chamber by a flexible tubular sleeve fixed to said sidewall andopening through said sidewall, a mercury switch in said float positionedso that pivotal up-and-down movement of said float as said chamber isfilled and emptied will close and open said switch, and lead wirespassing through said tubular sleeve to said switch and connected toenergize said heater when said switch is closed.